The invention relates to a television tuner for at least two frequency bands having a joint pre-amplifier and having a switchable and tunable band-pass filter circuit connected to the output of the pre-amplifier for the two frequency bands, preferably for the frequency range from VHF band I up to and including the hyper band. The invention further relates to an input circuit of a television tuner and a television turner having a joint antenna connection for two frequency ranges sweeping the frequencies from VHF band I up to and including the hyper band, a pre-circuit filter, a preamplifier circuit dimensioned for the two frequency ranges, and two independent band-pass filters dimensioned for a low and a high frequency range respectively and a subsequent mixer stage and intermediate frequency circuit.
In a known television tuner (DE-PS 29 29 901) a switchable pre-circuit filter is provided at a joint antenna connection and the output of the former is connected to a joint pre-amplifier. Behind the output of the pre-amplifier is connected a switchable band-pass filter circuit, also rated for two frequency ranges and whose resonant circuits each have two series-connected coils of which one can be short-circuited by DC-controlled band-switching diodes. The joint output of the band-pass filter circuit is connected to a mixer circuit. Accordingly, two switching elements are required for switchover of a combined band-pass filter circuit, and corresponding DC supply paths must be provided for these elements. These switching diodes represent capacitive and ohmic loads that not only adversely affect selection, but also restrict the frequency tuning range, so that tuning within a frequency range covering the VHF band I up to and including the hyper band cannot be swept.